Running svn checkout in cmd window needs manual intervention

Environment:
Installed ReactOS r63791 using bootcd

Steps to reproduce:
Download Apache Subversion 1.8.4 command line client from
http://www.visualsvn.com/files/Apache-Subversion-1.8.4.zip
into c:\downloads

Unzip using e.g. 7zip; go to bin path e.g.
cd c:\downloads\apache-subversion-1.8.4\bin

Check out SVN repository using svn
in a cmd window
mkdir c:\development\
mkdir c:\development\fpc
rem example is freepascal compiler; that's what I tested with
svn checkout http://svn.freepascal.org/svn/fpc/branches/fixes_2_6 c:\development\fpc

The bug:
Checkout progresses (downloads files) but you have to activate the cmd window by e.g. scrolling, moving the mouse around, pressing shift etc otherwise the svn download seems to halt (Virtualbox network adapter shows no activity; no new files checked out); moving the mouse etc restarts the process.